Marie Unna Hereditary Hypotrichosis Gene Maps to Human Chromosome 8p21 Near Hairless

The study identified that the gene responsible for Marie Unna hereditary hypotrichosis (MUHH), a rare autosomal dominant disorder affecting hair density and structure, was mapped to human chromosome 8p21. Genetic linkage analysis in a large Caucasian family revealed a significant LOD score, confirming the gene's location between markers D8S258 and D8S1739. Despite the proximity to the human hairless (Hr) gene, mutation analysis of Hr did not reveal any associated mutations, suggesting the involvement of other genes in this chromosomal region in hair growth control. The study highlighted the importance of chromosome 8p21 in understanding hair growth disorders.